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Khan Academy: Computer Science

khanacademy.org

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Re: Khan Academy: Computer Science

#41

Post by artursapek »

jeresig wrote: post #35
dag11 wrote: post #30

The videos for CS are brilliant. I don't think programming videos could possibly be more perfect than this. For example: http://www.khanacademy.org/cs/booleans/839898911 So you can scrub through the lesson and play and pause it, and the instructor can type code into the editor directly causing it to output on your screen in real-time. But the amazing outcome of this is that the viewer can pause the lesson at any time…

Awesome - glad you're enjoying it! One thing to note: If you make changes to the code and then hit play again right now the user's changes are lost (making sure that playback will continue to work). We definitely want to persist those changes in some way, automatically, although in the worst case the user can always make some changes and hit 'Save' and they'll be saved to their own account.

That's a pretty good worst case scenario. I wouldn't change how it works at all.

Re: Khan Academy: Computer Science

#42

Post by raldi »

jeresig wrote: post #35
dag11 wrote: post #30

The videos for CS are brilliant. I don't think programming videos could possibly be more perfect than this. For example: http://www.khanacademy.org/cs/booleans/839898911 So you can scrub through the lesson and play and pause it, and the instructor can type code into the editor directly causing it to output on your screen in real-time. But the amazing outcome of this is that the viewer can pause the lesson at any time…

Awesome - glad you're enjoying it! One thing to note: If you make changes to the code and then hit play again right now the user's changes are lost (making sure that playback will continue to work). We definitely want to persist those changes in some way, automatically, although in the worst case the user can always make some changes and hit 'Save' and they'll be saved to their own account.

Thanks for dropping in.

As long as you're here, I'd like to bring to your attention a UX issue that might deeply impact first impressions. If you visit the site for the first time and click the play button, there's a good chance that, immediately following this click, the mouse cursor will stray into the code area.

This causes the code to turn white, and so the viewer just sits there listening to the lesson and watching things change in the running-program frame, oblivious to the fact that the code is invisibly changing, too (one of the coolest parts of the product).

You might want to unfade the code and get rid of the "Pause" button if the cursor hasn't moved in a while, to ensure first-time visitors don't miss the awesome code-to-audio syncing.

Other than that, I'm super impressed with the site.

Re: Khan Academy: Computer Science

#43

Post by simonbrown »

dullcrisp wrote: post #29
recursive wrote: post #6

This looks like it has more to do with programming than computer science. That's a good thing, in my opinion, since I think programming is probably more generally useful. But it's a little misleading as the title.

I would really like to see something like a Khan Academy for introductory computer science. As it is, it seems there's nowhere to learn computer science basics at a below university level.

What about Coursera?

Re: Khan Academy: Computer Science

#44

Post by user911302966 »

Drawing? Animation? Games? ... "Wanna"?

Yes, this is how you bait a small child or idealistic young adult into wanting to "become a computer scientist when I grow up". Yes, it coerces pseudointerest in something. But, this isn't sustainable and it's not how participation in computing will be advanced.

Discrete maths aren't advertised by hyping up the life of a traveling salesman, and neither should computer science. The former attracts academics wishing to push bounds for humanity, fame, ego, etc.

Computer science is the youngest of the lot, so we ought to have no shortage of green kids studying and pushing understanding. Since we don't, I appreciate attempts such as this, but I think that history proves them to be misguided.

Re: Khan Academy: Computer Science

#45

Post by sirmarksalot »

jeresig wrote: post #35
dag11 wrote: post #30

The videos for CS are brilliant. I don't think programming videos could possibly be more perfect than this. For example: http://www.khanacademy.org/cs/booleans/839898911 So you can scrub through the lesson and play and pause it, and the instructor can type code into the editor directly causing it to output on your screen in real-time. But the amazing outcome of this is that the viewer can pause the lesson at any time…

Awesome - glad you're enjoying it! One thing to note: If you make changes to the code and then hit play again right now the user's changes are lost (making sure that playback will continue to work). We definitely want to persist those changes in some way, automatically, although in the worst case the user can always make some changes and hit 'Save' and they'll be saved to their own account.

My ideal scenario would be to have the student's code saved in a sideboard, while the teacher's code would take over the forefront. Sort of like a really minimalist branch feature.

If you could make it work with the layout, it would be really cool to have the student's code window physically move off to the side, indicating that the teacher was taking over, but their code would still be there whenever they wanted to get back to it.

Re: Khan Academy: Computer Science

#46

Post by pjscott »

Kiro wrote: post #7

So what's the difference between this and any other tutorials on the internet?

Try it. Go here, have a look around for a minute or two, maybe fiddle with some code:

http://www.khanacademy.org/cs/tutorials/drawing

It really improves on the classic style in two ways:

1. It's very easy to get started. There's no setup; just click a link.

2. The connection between the code and what it does is made very clear. The picture depends on the code, and changes when you change the code. There are sliders you can adjust for each integer literal. Bam!

This is exciting stuff.

Re: Khan Academy: Computer Science

#47

Post by vlad »

Great work, but I have some feedback about the first video shown to everyone who visits the Computer Science page.

1) It jumps right into talking about syntax of programming instead of showing screen shots of what a person will be able to build after completing the lessons, the benefits of learning about Computer Science, some cool problems they will know the answer to, etc, like Udacity does.

2) It is spoken way too fast. It's going to turn off almost all non-native english speakers, as well as confuse many english speakers.

3) As if that's not bad enough, anyone who turns on closed captioning to get a transcript will be even more confused, as YouTube's transcription is both messy and flashes quickly. It's so useless, you should look into disabling the CC button for the videos while looking into other approaches in the mean time.

Example:

"according to a common just by out of the two facets to the front and we call this commenting out coat now the fun we skipped and sometimes this can get away with the land was for".

4) When re-recording it, I hope the speaker (who is female) says "men and women" rather than "dudes" when talking about programmers several times. Lots of women have contributed to software development. Otherwise, she made some great jokes!

http://www.khanacademy.org/cs/1-welcome-to-codecanvas/882454...

Re: Khan Academy: Computer Science

#48

Post by vlad »

vlad wrote: post #47

Great work, but I have some feedback about the first video shown to everyone who visits the Computer Science page. 1) It jumps right into talking about syntax of programming instead of showing screen shots of what a person will be able to build after completing the lessons, the benefits of learning about Computer Science, some cool problems they will know the answer to, etc, like Udacity does. 2) It is spoken way too…

Maybe a great solution would be to allow other users to record their own explanations for the lesson, so that the viewer could choose (and vote up) the ones they like better (by clarity, preferred accent, a different human language altogether, etc.)

Re: Khan Academy: Computer Science

#49

Post by dudey »

vlad wrote: post #47

Great work, but I have some feedback about the first video shown to everyone who visits the Computer Science page. 1) It jumps right into talking about syntax of programming instead of showing screen shots of what a person will be able to build after completing the lessons, the benefits of learning about Computer Science, some cool problems they will know the answer to, etc, like Udacity does. 2) It is spoken way too…

Speaking slower would make the videos much longer, which would lose viewership. I'm in favour of having the presenter talk quickly, thus making the video shorter. The words are all spoken clearly; it's easy to pause and rewind if you need to.

Re: Khan Academy: Computer Science

#50

Post by dsawler »

brown9-2 wrote: post #27
jeresig wrote: post #17

Earlier quoted context omitted.

I disagree. We're working towards the goal of having a comprehensive Computer Science curriculum and this is just the first step. I talk more about our reasoning and methodology here: http://ejohn.org/blog/introducing-khan-cs/

I really love what is being done here so far, especially the voice overs and live code editor, but I think it might be helpful to first-time visitors to put some more of that info on the khanacademy.org/cs page as well. Right now, at first glance it just looks like the Khan "Computer Science" curriculum is solely about learning how to make drawings and animations with processing.js. It can be a bit confusing to the f…

This. Exactly. I was really confused. I've been trying to learn JS on an off for about a year. When I was shown the new CS program at Khan Academy today, I was instantly confused because...I was drawing pictures using processing.js. So..was I learning javascript or was I learning this processing.js that runs on top of javascript? As a beginner, I think it's super important you clarify this.
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